This invention relates to the mechanical construction and electrical interconnection of a modularly expandable programmable controller, and more particularly to an improved backplane unit for a programmable controller module.
Sensing devices are essential to factory automation, but the job of connecting them to prior art programmable controllers or host computers can be time-consuming and costly. There have been proposals in the prior art for modularly expandable controllers. However, these prior art structures do not accommodate readily the input/output wiring and are not as mechanically rugged as is advantageous for many applications.